During my nearly three decades as a celebrity fitness and nutrition expert, nothing drives me nuts more than the cliché, "Everything in moderation." This polarizing phrase paves the way for overeating, cravings and weight loss resistance.

Your body is a chemistry lab, not a bank account or a calorimeter. Everything from eating the wrong foods to chronic stress affects your body's chemistry. If you want to ditch that extra fat, you have to heal your body's chemistry.

The moderation myth fails to account for such biochemical complexity. It clings to an erroneous "calorie-is-a-calorie" mentality that then gives people license to eat things they shouldn't eat. No matter how well-intentioned someone is, there's no way to literally have your cake and eat it too.

As David Sciola recently pointed, no safe level exists for trans fats, high-fructose corn syrup or artificial sweeteners. Even the tiniest bit of these can wreak havoc. Likewise, if you have gluten intolerances or other food sensitivities, even a few bites of these foods can create problems.

Moderation ultimately creates these five obstacles that hijack fat loss and great health:

1. Moderation creates a slippery slope.

If a little bit is OK, then a little bit more is also OK. One cookie quickly turns into two and that weekly sugary muffin turns into a daily ritual. Or a few tablespoons of butter pecan become the whole container, and you guiltily promise you'll restart your diet tomorrow.

In his book The End of Overeating, Dr. David Kessler discusses how the sugar/salt/fat combination of most processed foods — think a big plate of chili cheese nachos from a chain restaurant — creates an addiction that makes it virtually impossible to eat these foods in moderation: "Until you have gained the upper hand over trigger foods, an attempt at moderation won't work." In other words, if you have a little bit, you will want a little bit more and more.

4. Moderation allows immune complexes to accumulate.

Food intolerances produce immune complexes that accumulate. If you eat a little bit of a highly reactive food like gluten or dairy each day, you build up more complexes. That "moderate" consumption over time can create chronic reactions from your gastrointestinal system and your immune system, ultimately impacting your weight.

5. Moderation ignores the serious damage that foods can do.

Food is information. What happens if you add a 100-calorie snack every afternoon to your diet? If you're using the bank-account model, you might think, Oh, it's just 100 extra calories each day. What harm could that do?

I realize how divisive "everything in moderation" can become, so I want your opinion. Do I have merit believing this mindset only creates failure or can moderation play a part in fast, lasting fat loss? Share your thoughts below.

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